عن أبى مسعود البدرى رضى الله عنه
قال: دعا رجل النبي صلى الله عليه وسلم لطعام صنعه له خامس خمسة، فتبعهم رجل، فلما بلغ الباب، قال النبي صلى الله عليه وسلم: «إن هذا تبعنا؛ فإن شئت أن تأذن له، وإن شئت رجع«قال: بل آذن له يا رسول الله»
A man prepared some food especially for the Prophet (sallallahu alayhi wa sallam) and invited him along with four others. But a man accompanied him. Having arrived at the door, Messenger of Allah (sallallahu alayhi wa sallam) said to the host, “This person has followed us. You may allow him, if you like, and if you like he will return.” He said: “O Messenger of Allah, I allow him, too.”.
Riyad as-Salihin 738, Book 3, The Book About the Etiquette of Eating, Hadith 12. 1 min read